My neighbors gave me their Philips DVDR3455H since they had lost the remote that originally came with it. Awesome, I thought, I have a universal remote I can program to work with it, way easier/cheaper than buying a new dvdrw/dvr, but sadly, after trying all the Philips codes listed for my Radio Shack 15-135 not one works. Any ideas what I could do, or what universal remote would work with it?
Thanks in advance!

Try one of THESE or get a JP1.3 cable to load the code into the 135. I think the Polaroid 2001G upgrade or the Philips 3576 upgrade on hifi-remote.com will work, but I'm not certain. If the 2001G code is correct, it's DVD 441 on a philips/magnavox universal like the PM725S. Any philips universal would be worth a try, but won't have every function.